Diffraction Techniques Research Articles

The effect of retained austenite on rolling/sliding contact fatigue of high carbon steel

Rolling contact fatigue (RCF) is significantly influenced by retained austenite (RA). To study the impact of the RA on fatigue life and pit formation, a high carbon steel was tested with three different RA levels ranging from 5 % to 23 % (volume fraction). The variations of the RA with respect to the number of cycles and along the depth were inspected by X-ray diffraction (XRD) technique. The microstructures before and after RCF were characterized by scanning electron microscopy (SEM) and electron backscatter diffraction (EBSD). The majority of RA was transformed into martensite at an early stage (before 3×104 cycles) in both surface and subsurface. And the remaining small fraction of RA was transformed during the rest of the testing life, with a final content lower than 5 %. As the depth increased, the rate of RA transformation decreased. The specimen with the highest RA level of 23 % showed the shortest life. The longest RCF life was seen in the specimen with a medium RA level of 15 % due to the formation of the well-developed hardened layer, which helps resisting the pit formation. Based on these observations, it was suggested that a medium level of RA is beneficial for the improvement of the RCF life of the present high carbon steel. The combined effect of the hardness and the RA acts together on resistance to pit formation.

Quasi-in-situ observation of fatigue crack growth behavior of friction stir welded 2024-T4 joint

Abstract This study presents a quasi-in-situ observation of the fatigue crack growth behavior in a friction stir welded 2024-T4 joint. The microstructure and fatigue properties of the joint were investigated using electron backscatter diffraction (EBSD) technique, scanning electron microscopy (SEM), and fatigue crack growth tests. The fatigue crack growth behavior of the joint was examined by conducting fatigue crack growth tests with different notch locations. The results show that the sample with the notch in the stir zone (SZ) exhibited the highest resistance to fatigue crack growth, followed by the notched samples of the Advancing side (AS) and Retreating side (RS) weldments. Microstructural observations showed a homogeneous microstructure with a fine grain size in SZ and it was observed that this fine-grained structure significantly enhanced the material's resistance to fatigue crack growth. The experimental results were further analyzed using the Paris model to provide a quantitative understanding of the crack growth behavior. The study underlines the impact of microstructural characteristics and notch location on the fatigue performance of the weldment. Overall, the quasi-in-situ observations and experimental findings contribute to a comprehensive understanding of the fatigue crack growth behavior in friction stir welded 2024-T4 joints.

Mechanochemically Robust LiCoO2 with Ultrahigh Capacity and Prolonged Cyclability.

Pushing intercalation-type cathode materials to their theoretical capacity often suffers from fragile Li-deficient frameworks and severe lattice strain, leading to mechanical failure issues within the crystal structure and fast capacity fading. This is particularly pronounced in layered oxide cathodes because the intrinsic nature of their structures is susceptible to structural degradation with excessive Li extraction, which remains unsolved yet despite attempts involving elemental doping and surface coating strategies. Herein, we develop a mechanochemical strengthening strategy through gradient disordering structure to address these challenges and push the LiCoO2 layered cathode approaching the capacity limit (256 mAh g-1, up to 93% of Li utilization). This innovative approach also demonstrates exceptional cyclability and rate capability, as validated in practical Ah-level pouch full cells, surpassing the current performance benchmarks. Comprehensive characterizations with multiscale X-ray, electron diffraction and imaging techniques unveil that the gradient disordering structure notably diminishes the anisotropic lattice strain and exhibits high fatigue resistance, even under extreme delithiation states and harsh operating voltages. Consequently, our designed LiCoO2 cathode impedes the growth and propagation of particle cracks, and mitigates irreversible phase transitions. This work sheds light on promising directions towards next-generation high-energy-density battery materials through structural chemistry design. This article is protected by copyright. All rights reserved.

Twinning–Detwinning-Dominated Cyclic Deformation Behavior of a High-Strength Mg-Al-Sn-Zn Alloy during Loading Reversals: Experiment and Modeling

The deformation behavior of a high-strength Mg-Al-Sn-Zn alloy under loading reversals has been thoroughly examined through a combination of experimental measurements and crystal plasticity modeling. We focused on an age-treated alloy fortified by distributed Mg2Sn particles and Mg17Al12 precipitates, which underwent two distinct loading cycles: tension-compression-tension (TCT) and compression-tension-compression (CTC), aligned with the extrusion direction (ED). The initial and deformed microstructures of the alloy were analyzed using the electron backscattering diffraction (EBSD) technique. Notably, the alloy displays tensile and compressive yield strengths (YS) of 215 MPa and 160 MPa, respectively, with pronounced anelastic behavior observed during unloading and reverse loading phases. Utilizing the elasto-viscoplastic self-consistent model incorporating a twinning–detwinning scheme (EVPSC-TDT), the cyclic stress–strain responses and resultant textures of the alloy were accurately captured. The predicted alternation between various slip and twinning modes during plastic deformation was used to interpret the observed behaviors. It was found that prismatic <a> slip plays an important role during the plastic deformation of the studied alloy, and its relative activity in tensile loading processes accounts for up to ~66% and ~67% in the TCT and CTC cases, respectively. Moreover, it was discerned that detwinning and twinning behaviors are predominantly governed by stresses within the parent grain, and they can concurrently manifest during the reverse tensile loading phase in the TCT case. After cyclic deformation, the area fractions of residual twins were determined to be 7.51% and 0.93% in the TCT and CTC cases, respectively, which is a result of the varied twinning–detwinning behavior of the alloy in different loading paths.

Trivalent Gd incorporated Zn2SiO4 phosphor material for EPR and luminescence investigations

Abstract Zn2SiO4:Gd3+ powder was obtained by the sol–gel preparation technique and then characterized by using Fourier-transform infrared spectroscopy and X-ray diffraction techniques. The sample exhibited photoluminescence in the ultraviolet spectral zone with a maximum emission wavelength of 314 nm. Ultraviolet emission in the range of 305–320 nm is also called ultraviolet-B emission. This UV range emission is used in lamps for skin treatment and phototherapy. The electron paramagnetic resonance spectrum recorded for the Zn2SiO4:0.015Gd3+ phosphor revealed g values of 3.46, 2.64, and 2.20, confirming the presence of Gd3+ ions in the small ligand field. Furthermore, Gd3+ ions attain tetrahedral symmetry in the prepared host compound.

Unrecoverable lattice rotation governs structural degradation of single-crystalline cathodes.

Transitioning from polycrystalline to single-crystalline nickel-rich cathodes has garnered considerable attention in both academia and industry, driven by advantages of high tap density and enhanced mechanical properties. However, cathodes with high nickel content (>70%) suffer from substantial capacity degradation, which poses a challenge to their commercial viability. Leveraging multiscale spatial resolution diffraction and imaging techniques, we observe that lattice rotations occur universally in single-crystalline cathodes and play a pivotal role in the structure degradation. These lattice rotations prove unrecoverable and govern the accumulation of adverse lattice distortions over repeated cycles, contributing to structural and mechanical degradation and fast capacity fade. These findings bridge the previous knowledge gap that exists in the mechanistic link between fast performance failure and atomic-scale structure degradation.

Sublimation‐Induced Vapor Deposition of Cyanuric Acid‐Melamine Supramolecular Single Crystals on Surfaces

AbstractHerein, a low‐temperature sublimation‐based vapor deposition (SVD) method is developed to synthesize hexagonal crystal plates of cyanuric acid‐melamine (CAM) with outstanding crystallinity. Through meticulous design of the reaction apparatus and careful selection of source materials, substrate‐confined SVD in a tube furnace is explored to grow single crystals of CAM in hexagonal shapes. Additionally, the orientation preference of the (202) facet is revealed, corresponding to the 2D arrangement of the H‐bonded network, of single‐crystalline plates on surfaces using selected area electron diffraction and X‐ray diffraction techniques. By employing atomic force microscopy and scanning electron microscopy for topography characterization, a mechanism of three‐stage step‐growth crystallization is proposed, including nucleation, in‐plane expansion, and out‐of‐plane growth. Furthermore, it is found that the interactions among melamine molecules in CAM synthesized via SVD are more intense compared to those in CAM synthesized via water‐based methods, as evidenced by infrared and photoluminescent spectra studies. Subsequent nanoindentation tests on the (202) facet of CAM single‐crystalline plates reveals a reduced modulus and hardness of 12.8 and 0.82 GPa, respectively. This methodology addresses the longstanding challenge of synthesizing hexagonal CAM single crystals and provides valuable insights for the fabrication of functional organic crystalline materials.

Characterization of Electrochemical and Biocompatibility of Zinc Oxide Coating Electrodeposited on Comercial Pure Titanium Alloy

This study examines how the duration of electrodeposition affects the morphology and electrochemical characteristics of zinc oxide coatings applied to a pure titanium substrate. The morphology of the coating and the phases present within it were analyzed using a scanning electron microscope and the X‐ray diffraction technique. The coating’s resistance to corrosion in a phosphate‐buffered saline solution was evaluated using two electrochemical methods: impedance spectroscopy and potentiodynamic polarization tests. The surface roughness of the coated samples was assessed using interferometry. The results demonstrate that an increase in electrodeposition time, ranging from 150 to 1200 seconds, leads to an enhanced texture intensity in the (0002) and (010) planes of the ZnO coating. Furthermore, the thickness of the ZnO crystals and surface roughness increases by factors of 3.25 and 2.79, respectively, as the deposition time is extended. This extended duration results in the formation of larger needle‐shaped and flower‐like ZnO crystals, leading to a significantly non‐uniform structure. Correspondingly, the corrosion rate also increases as the electrodeposition time is extended from 150 to 1200 seconds, rising from 0.001951 to 9.117 µm/year. The lowest corrosion rate (1.654 µm/year) is achieved in coatings deposited for 300 seconds using a potential of 3 V.This article is protected by copyright. All rights reserved.

Establishing the Morphotropic Phase Boundary in van der Waals Ferroelectrics

Abstract The formation of morphotropic phase boundaries (MPBs) is a pivotal strategy in piezoelectric ceramics and crystals, primarily used to enhance the electromechanical coupling. However, the application of this strategy in van der Waals (vdW) piezoelectrics and ferroelectrics has been limited, largely due to challenges in achieving phase coexistence and enabling possible polarization rotation. In this study, we address this gap by synthesizing a Selenium doped vdW ferroelectric, CuInP2(S1-xSex)6, with a doping range of 0 ≤ x ≤ 0.15, to create an MPB. Our findings indicate the presence of an MPB near x=0.05, situated between monoclinic and trigonal phases. This boundary was confirmed using X-ray diffraction and transmission electron microscope techniques. Remarkably, the composition at x=0.05 shows a high dielectric constant (εr=13.8) and an impressive local effective piezoelectric coefficient (d33eff=51 pm/V) at 80 K. Additionally, an unusual softening of the Young’s modulus was observed near MPB. These results are crucial for enhancing electromechanical coupling in vdW layered materials and herald new avenues for the design and optimization of piezoelectric and electromechanical properties in these materials.

Wear Resistance Behavior of Low-, Mid-, and High-Phosphorus Electroless Ni-P Coatings Heat-Treated in the Air Environment

The high-temperature heat treatment of electroless nickel–phosphorus (Ni-P) coatings in an air environment, and its consequences have scarcely been investigated. This work investigated tribological characteristics of the high-temperature, heat-treated, electroless Ni-P coatings on steel substrates with low-, mid-, and high-phosphorus content for which the average phosphorus content was 2.4 wt.%, 7.1 wt.%, and 10.3 wt.%, respectively. X-ray fluorescence and energy dispersive spectroscopy were implemented to determine the phosphorus content of the coatings. The oxidation of Ni and the formation of the NiO layer on the coating surface was confirmed by the X-ray diffraction technique. A reciprocating sliding method on a ball-on-flat system was utilized to evaluate the coating’s friction and wear behavior. Among the coatings with varying phosphorus content, a high hardness of 1086 HV was found for high-phosphorus coating when heat-treated at 400 °C in an air environment, and that was decreased to 691 HV when heat-treated at 650 °C. The oxidation of nickel in the electroless Ni-P coating occurred when heat-treated at 400 °C in an air environment, and this phenomenon was increased more when the temperature was increased to 650 °C. The characteristics of the NiO layer that formed on the surface of the heat-treated electroless Ni-P coating were influenced by the concentration of phosphorus, which caused different colors of NiO to be seen on the Ni-P coating surface. A greenish black NiO layer on the low-phosphorus and black NiO layer on the mid- and high-phosphorus Ni-P coating was developed during heat treatment at 650 °C in an air atmosphere. The adhesion and tribological characteristics of the Ni-P coatings were affected by the NiO layer developed on the heat-treated Ni-P coating surfaces. The Ni-P coatings with mid- and high-phosphorus content showed enhanced wear-resistance characteristics when they underwent heat treatment in an air atmosphere at the high temperature of 650 °C. The wear volume obtained for as-plated mid-phosphorus and high-phosphorus Ni-P coatings was 0.111 mm3 and 0.128 mm3, respectively, and that was reduced to 0.031 mm3 and 0.051 mm3, respectively, after the high-temperature heat treatment.

Improving the optical and dielectric characteristics of PVA/PVP/PEG/ZnWO4/CdS blends

This work aims to create novel nanocomposite blended polymers by incorporating (1−x)ZnWO4-xCdS into poly (vinyl alcohol) (PVA)/polyvinyl pyrrolidone (PVP)/polyethylene glycol (PEG) blend to employ these nanocomposites in various optoelectronic applications. This study focused on investigating the structural, optical and electrical features of PVA/PVP/PEG/(1−x)ZnMn2O4-xCdS blends. The x-ray diffraction and scanning electron microscope techniques were used to explore the structure and morphology of the formed samples. The structure and percentages of ZnWO4 and CdS in different fillers were performed using Rietveld method. The doped blends exhibited significant absorption of UVA and UVB types. The greatest amounts of absorption were observed when the filler contained 25 % CdS. The direct and indirect optical band gaps of the doped blend became 5.02 and (1.88, 2.37) eV as the amount of CdS became 25 % in the filler sample. The refractive index, optical dielectric constant, optical conductivity, and nonlinear optical parameters are affected by the amount of CdS in the fillers. The fluorescence spectra for the blends affected by the excitation wavelength and amount of CdS in the filler. The maximum energy density of the doped blend was reached when the amount of CdS in the filler reached 25 %. The purities of emitted color in the undoped blend are 83 % and 74 % under excitation wavelengths of 317 nm and 380 nm. The purity of the blend experienced a slight change when loaded with filler samples. As the ZnWO4 doping of the PVA/PVP/PEG blended polymer rose, its electrical dielectric constant and ac conductivity first enhanced and then irregularly declined as the filler's CdS content rose. Incorporating (1−x)ZnWO4-xCdS into the nanocomposite enhanced their optical and electrical properties, making them a potential material for flexible optoelectronic and energy storage uses.

Tailored Ni‐Zn‐Cu ferrite/EPDM nanocomposites: Synthesis, characterization, and multifaceted properties for mechanical and electrical applications

AbstractIn this study, we prepared Ni‐Zn‐Cu Fe2O4 ferrite/ethylene propylene diene monomer (EPDM) rubber nanocomposites with enhanced mechanical and electrical properties. First, Ni‐Zn‐Cu Fe2O4 ferrite nanoparticles were synthesized with a tailored composition of NiZn(0.3)Cu(0.2)Fe2O4(2). Subsequently, these nanoparticles were incorporated into the EPDM rubber matrix through a two‐roll mixing mill. Scanning electron microscopy and x‐rays diffraction techniques were used to explore their morphology and structure. Fourier‐transform infrared spectroscopy was used to identify metal‐oxygen bonds in the nanoparticles and their incorporation in the nanocomposites. Similarly, curing properties, including optimum cure time, scorch time, and torque profiles, were evaluated using a moving die rheometer. While, mechanical properties of these composites, such as tensile strength and Young's modulus, were determined with a universal testing machine. Tensile strength improved from 0.11 MPa to 0.22 MPa (100% increase), whereas, the Young's modulus increased from 0.03 MPa to 0.052 MPa (86% increase). Additionally, we investigated the dielectric properties of these nanocomposites, encompassing permittivity, resistivity, and dielectric constant, using a dielectric properties analyzer. Our findings revealed a significant reduction in dielectric resistivity of nanocomposites (from 33.2 GΩ to 23.38 GΩ) upon the introduction of Ni‐Zn‐Cu Fe2O4 ferrite nanoparticles, indicating the formation of a continuous nanofiller network within the EPDM matrix. Interestingly, as the nanofiller loading increased, both dielectric permittivity and dielectric constant exhibited a gradual rise. The permittivity value increased from 2.31 to 2.39 (Fm−1), while the dielectric constant increased from 0.0091 to 0.0179.Highlights Synthesized Ni‐Zn‐Cu Fe2O4; tuned composition NiZn(0.3)Cu(0.2)Fe2O4(2). Integrated ferrite into EPDM; optimized mixing for enhanced properties. Employed SEM, XRD, and FTIR; revealed morphology, structure, and bonding. Evaluated curing using MDR; unveiled optimal time and torque profiles. Explored dielectric properties; demonstrated reduced resistivity, heightened permittivity.

UV-Irradiation Effects on the Structural, Optical and Electrical Characteristics of Soft Blended Polymeric Materials Loaded with Multi-Walled Carbon Nanotubes (MWCNTs)

Undoped and doped polyvinylpyrrolidone/carboxy-methyl cellulose/zinc sulfide/nickel oxide (PVP/CMC/ZnS/NiO) nanocomposite blends with multi-walled carbon nanotubes (MWCNTs) were prepared using sol-gel and solid-state reactions and casting techniques. Various blends were formed and their composition and morphologies were characterized using X-ray diffraction (XRD) and scanning electron microscope (SEM) techniques. The structures of the nano-fillers were examined using the XRD technique. The influence of the concentrations of MWCNTs on the linear and nonlinear optical parameters of PVP/CMC/ZnS/NiO nanocomposite blends was examined. The optical band gap energies were decreased from (direct, indirect: 5.31, 5.06) eV for undoped blends to 4.38 and 3.34 eV for the blends doped with the highest concentration of MWCNTs (0.15 wt%). The refractive indices of the various blends were calculated based on the obtained optical band gap energies using various models. The effect of MWCNTs concentrations on the dielectric constants, energy density, electric modulus and ac conductivity at room temperature of the PVP/CMC/0.5ZnS-0.5NiO/x wt% MWCNTs samples were explored using an Inductance, L, Capacitance, C, and Resistance, R (LCR) meter bridge.

Coprecipitation Strategy for Halide-Based Solid-State Electrolytes and Atmospheric-Dependent In Situ Analysis.

In the continuous pursuit of an energy-efficient alternative to the energy-intensive mechanochemical process, we developed a coprecipitation strategy for synthesizing halide-based solid-state electrolytes that warrant both structural control and commercial scalability. In this study, we propose a new coprecipitation approach to synthesized Li3InCl6, exhibiting both structural and electrochemical performance stability, with a high ionic conductivity of 1.42 × 10-3 S cm-1, comparable to that of traditionally prepared counterparts. Through the in situ synchrotron X-ray diffraction technique, we unveil the stability mechanisms and rapid chemical reactions of Li3InCl6 under dry Ar, dry O2, and high-humidity atmosphere, which were not previously reported. Furthermore, the fast reversibility capability of moisture-exposed Li3InCl6 was tracked under vacuum, revealing the optimal recovery conditions at low temperatures (150-200 °C). This work addresses the critical challenges in structural engineering and sustainable mass production and provides insights into chemical reactions under real-world conditions.

Effect of surfactants on the degree of polydispersity of a suspension of polystyrene latex spheres

The problem of satisfying the needs of the domestic market of the Russian Federation for creating domestic particle size standard reference materials in liquids to ensure uniformity in measurements of the granulometric composition of aerosols and powdery substances is considered. It is known that, under various conditions, monodisperse suspensions of polystyrene latex spheres can be synthesized, both monodisperse and polydisperse samples being obtainable. The effect of the composition and solubility of surfactants in a styrene-based water emulsion on the particle size of suspensions obtained as a result of emulsion polymerization, and their polydispersity, has been investigated. The metrological characteristics of polystyrene suspensions based on sodium, potassium, and lithium laureths synthesized in this study were determined using dynamic light scattering and laser diffraction techniques. It has been found that the size and degree of polydispersity of particles in suspensions based on lauric acid salts is primarily influenced by the solubility of the surfactant and the surface tension of the interfacial layer formed between styrene and water at the time of particle formation. The effect of the rate of reaction, as well as the concentration of surfactants, on the size and polydispersity of the synthesized particles, has been studied. It has been found that when potassium persulfate is used as the initiator in the reaction, particle size distributions are monodisperse for suspensions based on sodium or potassium laureate. The polydispersity degree of lithium laureate-based suspensions is approximately 1.5 to 2 times higher compared to other suspension samples. When azoisobutyronitrile is used as an initiator, all suspensions samples are monodisperse. It has been experimentally determined that the achievement of monodisperse samples is due to the polymer-monomer particle formation time, which is comparable to the monomer transformation rate. The results obtained will be utilized in the development and establishment of particle size standard reference materials for storage and reproduction of particle size values within a liquid medium.

Multiple-angle incidence resolution spectrometry (MAIRS): applications in nanoarchitectonics and applied physics

Abstract The cutting-edge thin film studies using the multiple-angle incidence resolution spectrometry (MAIRS) are introduced from the principle to forefront applications in a wide variety of research fields covering semiconductor material with respect to nanoarchitectonics. MAIRS basically reveals quantitatively optical anisotropy in thin films, which is mostly used for quantitative molecular orientation analysis of each chemical group for chemistry purposes. This works powerfully especially when the material has poor crystallinity that cannot be analyzed by X-ray diffraction analysis. As a matter of fact, MAIRS works as a role that compensates for the diffraction techniques, and the combination of MAIRS and the diffraction techniques has already established as the most powerful technique not to miss the molecular aggregation structure in thin films. In this review, in addition, another application for physics purposes is also introduced where phonon in thin films is discriminated from normal infrared absorption bands by using the MAIRS technique.

Designing a Phenalenyl-Based Dinuclear Ni(II) Complex: An Electrocatalyst with Two Single Ni Sites for the Oxygen Evolution Reaction (OER).

A new dinuclear Ni(II) complex 1, [Ni2II(dtbh-PLY)2], is synthesized from 9-(2-(3,6-di-tert-butyl-2-hydroxybenzylidene)hydrazineyl)-1H-phenalen-1-one, dtbh-PLYH2 ligand, and structurally characterized by various analytical tools including the single-crystal X-ray diffraction (SCXRD) technique. In the solid state, both Ni(II) metal centers in complex 1 exist in a distorted square planar geometry and display the presence of rare Ni···H-C anagostic interactions to form a one-dimensional (1-D) linear motif in the supramolecular array. Complex 1 is further stabilized in the solid state by π-π-stacking interactions between the highly delocalized phenalenyl rings. The redox features of complex 1 have been analyzed by the cyclic voltammetry (CV) technique in solution as well as in the solid state, revealing the crucial involvement of both the Ni(II) metal centers for undergoing quasi-reversible oxidation reactions on the application of an anodic sweep. A complex 1-modified glassy carbon electrode, GC-1, is employed as an electrocatalyst for oxygen evolution reaction (OER) in 1.0 M KOH, giving an OER onset at 1.45 V, and very low OER overpotential, 300 mV vs the reversible hydrogen electrode (RHE) to reach 10 mA cm-2 current density. Furthermore, GC-1 displayed fast OER kinetics with a Tafel slope of 40 mV dec-1, a significantly lower Tafel slope value than those of previously reported molecular Ni(II) catalysts. In situ electrochemical experiments and postoperational UV-vis, Fourier transform infrared (FT-IR), scanning electron microscopy-energy-dispersive X-ray spectroscopy (SEM-EDS), and X-ray photoelectron spectroscopy (XPS) studies were performed to analyze the stability of the molecular nature of complex 1 and to gain reasonable insights into the true OER catalyst.

Synthesis of nano magnetic chitosan modified with acrylamide schiff’s base for simultaneous removal of Cu(II) and Co(II) from waste water samples

ABSTRACT A magnetic nano sorbent based on the functionalization of magnetic chitosan with acrylamide was synthesized for Cu(II) and Co(II) removal from wastewater samples. To characterize the magnetic nano sorbent, they have been applied from Fourier transform infrared spectroscopic analysis (FTIR), X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques. The effective parameters of Cu(II) and Co(II) adsorption on magnetic nano sorbent such as pH of the solution, adsorbent dose, contact time and sample volume, were optimized. Also, the effective parameters on Cu(II) and Co(II) desorption conditions (type and volume of elution solvent) were optimized. The isotherms and kinetics models for the adsorption of Cu(II) and Co(II) on the magnetic nano sorbent were studied. The data were well-fitted with the Langmuir isotherm and pseudo-second-order model. The maximum adsorption capacities for Cu(II) and Co(II) were 165.4 and 159.9 mg g-1, respectively. Also, the thermodynamic parameters were studied. Application of magnetic nano sorbent for 4 times of use was acceptable. For the real samples, the percentage of recovery was higher than 97% and RSD (%) was between 1.4% and 2.7%. Finally, the magnetic nano sorbent exhibited high performance in removing the Cu(II) and Co(II) from wastewater samples.

Supramolecular Assemblies in Mn(II) and Zn(II) Metal–Organic Compounds Involving Phenanthroline and Benzoate: Experimental and Theoretical Studies

Two new Mn(II) and Zn(II) metal–organic compounds of 1,10-phenanthroline and methyl benzoates viz. [Mn(phen)2Cl2]2-ClBzH (1) and [Zn(4-MeBz)2(2-AmPy)2] (2) (where 4-MeBz = 4-methylbenzoate, 2-AmPy = 2-aminopyridine, phen = 1,10-phenanthroline, 2-ClBzH = 2-chlorobenzoic acid) were synthesized and characterized using elemental analysis, TGA, spectroscopic (FTIR, electronic) and single crystal X-ray diffraction techniques. The crystal structure analysis of the compounds revealed the presence of various non-covalent interactions, which provides stability to the crystal structures. The crystal structure analysis of compound 1 revealed the formation of a supramolecular dimer of 2-ClBzH enclathrate within the hexameric host cavity formed by the neighboring monomeric units. Compound 2 is a mononuclear compound of Zn(II) where flexible binding topologies of 4-CH3Bz are observed with the metal center. Moreover, various non-covalent interactions, such as lp(O)-π, lp(Cl)-π, C–H∙∙∙Cl, π-stacking interactions as well as N–H∙∙∙O, C–H∙∙∙O and C–H∙∙∙π hydrogen bonding interactions, are found to be involved in plateauing the molecular self-association of the compounds. The remarkable enclathration of the H-bonded 2-ClBzH dimer into a supramolecular cavity formed by two [Mn(phen)2Cl2] complexes were further studied theoretically using density functional theory (DFT) calculations, the non-covalent interaction (NCI) plot index and quantum theory of atoms in molecules (QTAIM) computational tools. Synergistic effects were also analyzed using molecular electrostatic potential (MEP) surface analysis.

Experimental Investigation of Phase Equilibria in the Al–Mo–Hf Ternary System at 400 °C and 600 °C

This study investigates the phase equilibria of the Al-Mo-Hf ternary system at 400 °C and 600 °C using X-ray diffraction (XRD) and electron probe microanalysis (EPMA/WDS) techniques. Seven three-phase and five two-phase regions were identified at 400 °C, while eight three-phase and four two-phase regions were identified at 600 °C. Despite variations in the solid solubility ranges of certain compounds, the distribution of phase zones in the isothermal cross-section remained consistent at both temperatures. Using the experimental results and logical deductions, isothermal cross-sections were constructed for the Al-Mo-Hf ternary system at 600 °C and 400 °C.